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POWR-SPEED® High-Speed Fuses

Maintain Critical Uptime with POWR-SPEED High-Speed Fuses

At the heart of your power electronics designs are power semiconductors. Feel confident that your critical power semiconductors are protected against short circuits when you specify POWR-SPEED high-speed fuses, which include multiple series designed for different applications.

These high-speed semiconductor fuses are specifically designed to have the short-circuit characteristics necessary for protecting semiconductor devices: low energy let-through (l2t), low peak currents (IPEAK), low-arc voltage and high heat dissipation. High-speed fuses are the only type of circuit protection device that can protect them from overcurrent faults due to their low energy let-through characteristics.

Watch an overview of how POWR-SPEED High-Speed Fuses deliver optimized performance and efficiency.

The POWR-SPEED Difference

Design engineers have trusted Littelfuse power protection expertise for over 30 years. You can count on receiving complete technical data and application support, making it easy to specify POWR-SPEED high-speed fuses. Plus, with a broad range of ratings and styles available, POWR-SPEED gives you the flexibility to drop in replacements for competitor semiconductor fuses.

  • Speed: Designed to provide fast, extreme current limitation
  • Performance & efficiency: Optimized for both
  • Reliability: Advanced construction prevents sand leakage
  • Low watt loss: Saves energy wasted during operations

PSR and QS Overview


PSX Overview


Typical Applications for POWR-SPEED High-Speed Fuses

Industrial System

  • High-power stack assemblies
  • Variable frequency drives
  • Inverters / UPS
  • Power supplies

Renewable Energy

  • Battery racks
    • Battery management system
    • DC common bus
  • Inverters
    • DC input side
    • AC output

Additional Applications for POWR-SPEED High-Speed Fuses

  • Food and beverage
  • Cranes and heavy-lifting equipment
  • Factories
  • Furnace / smelting equipment
  • Processing industries
  • Pulp and paper
  • Rubber extrusion equipment
  • Wastewater treatment plants
  • Uninterrupted Power Supply (UPS) manufacturers

POWR-SPEED Fuses Application Guide


Download our 52-page application guide to learn more about high-speed fuseology, plus sizing, application, and installation guidelines.

POWR-SPEED Success Stories

Integrator Helps Utility Lower Operating Costs

A battery energy storage system (BESS) integrator wanted to provide its utility customer the ability to respond faster to increases in power demand while lowering its operating costs. The integrator selected lithium ion batteries to address the utility’s requirement for a higher-capacity battery pack but needed a fast fuse with a higher short-circuit current rating to support it.

With the protection of Littelfuse PSR high-speed semiconductor fuses, the integrator could reduce the dc combiner count and add more battery banks, creating a faster and more cost-efficient power demand response for the utility.

Key Selection Criteria for POWR-SPEED High-Speed Fuses

Case Size & Termination

  • Meets IEC 60269-4 Standard dimensions specification.
  • Mechanical dimensions match competitor product.
  • Availability of standard mounting terminations.
    • Flush End (Metric/Inches)
    • DIN Style (80mm, 110mm)
    • Bolted Style (Short, Long)

Standards & Certifications

  • Compliance with US & Canadian Requirements (UL248-13).
  • IEC 60296-4, Class aR.
  • GB/T 13539.4-2016.

Environmental Compliance

  • CE Certified.
  • RoHS Compliant.
  • REACH Compliant (Europe).

POWR-SPEED High-Speed Fuse Product Details

POWR-SPEED PSR Series square-body fuses are specifically designed for protection of power semiconductor devices such as diodes, TRIACs, IGBTs, SCRs, MOSFETs and other solid state devices that are typically designed into power conversion and power conditioning equipment.

Download the datasheet or visit the product page for specifications, part comparison, sample ordering, agency approvals, and complete product details.

PSR Flush End


PSR Bolted Blade

POWR-SPEED PSX Series high-speed fuses are extremely fast-acting and offer high-speed performance up to 1500 V dc. Ranging from 80 A to 1400 A in the smallest NH XL package sizes on the market, these fuses and are available flush-end style, DIN-style and bolted-blade style mounted terminations. Plus, visual blown fuse indication is standard on all fuses and optional micro-switch is available for external indication.

Download the datasheet or visit the product page for specifications, part comparison, sample ordering, agency approvals, and complete product details.

PSX Series

POWR-SPEED QS Series round-body fuses are designed with high-performance silver fuse elements, which combine with a hardened silica filler to provide enhanced system protection.

Download the datasheet or visit the product page for specifications, part comparison, sample ordering, agency approvals, and complete product details.

Download Our High-Speed Semiconductor Products Catalog

Browse the full 64-page catalog of POWR-SPEED high-speed fuses and accessories with complete ordering information and a convenient cross-reference guide.


Contact POWR-SPEED Sales

For help from our sales team in choosing the right high-speed fuse for your semiconductor application, complete the form below or call 1-800-TEC-FUSE.